Submersible pumping unit



July 14, 1942. L. YOST SUBMERSIEBLE PUMPING UNIT Fil ed March 24, 1941.

Lloyd Ybsz INVENTOR. d

ATTORNEY.

,I are first assembled in relatively short sleeves,

Patented July 14, 1942 UNITED STATES sunmmsmm PUMPING om'r Lloyd Yost, Lo: Amgeles, Calm, asslgnor MA. 0. .smith Corporation, Milwaukee, Win, a. corporation of New York Application March 24, 1941, Serial No. 384,885

, 4 Claims.

This invention relates to a submersible pumping unit such as are used in pumping oil wells.

An object of the invention is to provide a. structure in which the threaded joints entering into its. construction are subjected to a torque This and other objects of the invention will be clear from the following detailed description and the accompanying drawing in which:

Figure l is a longitudinal section showing the made up by turning on head I5 while holding the nose]. Since all the threaded joints are 01 the constituent-parts before the final weld is made; Fig. 2 is an enlarged top plan view of Fig. 1; and V Fig. 3 is an enlarged longitudinal sectional view through the upper end after the weld is completed.

Pumping .units for which this invention is adapted. have an outer casing inclosing the mechanism. This may include an electric motor, a

, sleeve and may have an outlet It for attachment to the tubing that is to receive the oil pumped by the unit, and a conduit I1 for a cable to convey electrical energy to the electric motor 5 which drives the pump.

tending to screw them together.

\ With the sleeves all joined together, the inner assembly is placed in the outer casing and v 3 threaded joint 9 between the lower end of thesleeve 4 and the. nose 2 of the,outer casing is same sense, either right hand or left hand, turning the head will tighten all the joints.

When the joints have been made up as tightly 16 as possible and easing I welded to the nose 2,

the latter is gripped or otherwise secured against rotation, and a torque is applied to the upper end of the casing I to twist it throughan angle that is smaller than the greatest torsional deflection pump driven by the electric motor, a hydraulic 20 that canbe obtained without exceeding the elastic motor, and a crude oil pump, and still other items of equipment depending upon the particular type of pumping unit used. The outer casing may extend for the whole length otthe unit, or it may extend for only a part of its length. The principles involved are the same in 3 either event.

Referring to the drawing, the outer casing I extends upward from a nose 2 welded to it. Thenose may be at the bottom of the complete unit, or it may, as shown in the drawing, have screw threads 3 for the attachment of another outer casing, with additional items of equipment, For convenience in assembly, the pieces of equipment that are destined to go into the outer casing 4, 5, 6, 1, and 8. No details are shown in the drawing with respect to the nature of the equipment used or the manner in'which it is secured in the sleeves since these are features which form no partof this invention.

The sleeves are of such length, iorm, and number as are needed to support the equipment that enters into the construction of the pumping unit; andare' provided with screwthreads 9, III, II, I2, I3 and I4 to join the different sleevesto each other or to other parts. The threads should all be of the same sense, that is, all right hand threads, or all left hand threads. Ordinarily right hand threads will be preferred as being the more usual form. I

When the equipment has been assembled and secured to the individual sleeves, the sleeves are joined together by making up joints III, I I, I2 and I3. The head I5 is also screwed into the upper sleeve. The head closes. the upper end of the threads, the head I5 must be turned clockwise to tighten the threads, see Fig. 2, and the casing I turned counterclockwise to apply the torqu While the outer casing is held twisted, th head I5 is secured to the upper end of the casing I' as by a weld I8.- Upon completion of the weld, the

torque is released. casing I to return to its original undeflected position results in the spring tension of the casin tending to tighten the threaded joints and insures that they will not be loosened by vibration during the life of the pumping unit.

I claim:

1. In a deep well pumping unit, an outer casing, an inner assembly composed of sections joined by screw threaded joints all of the same sense, and joints uniting the inner assembly to the outer casing at the ends of the latter, the outer casing being elastically deflected between the joints 'in such a direction that its tendency to return to its initial configuration operates to tighten the screw threaded joints.

2. In a deep well pumping unit, an outer casing, an inner assembly composed of sections joined so by screw threaded joints all of the same sense,

a threaded joint of the same sense joining the inner assembly and the outer casing at one end, and a welded joint between the inner assembly and the outer casing at the other end, the outer casing being elastically deflected between its connections to the inner assembly in such a direction The tendency of the tubular I that its tendency to return to its initial configw ration operates to tighten the screw threaded joints.

3. In a composite tubular structure, an outerv tube, an inner assembly composedoi. sectionsjoined by screw threaded joints all of the same sense, and joints uniting the inner assembly to the outer tube, the outer tube being elastically 4. In a composite tubular structure, two concentric members, a threaded joint between the two members, and a welded joint between, them, at least one of the two members being elastically deflected between the joints connecting it to the other with the direction of deflection such that the tendency of the deflected member to return to its initial configuration operates to tighten the threaded joint.

LLOYD YOST. 

